DARWINISM TO-DAY
may provide the most detailed physico-chemical analysis of some
bodily process: but his description will be incomplete unless he takes
account of its evolutionary history as well.
The unifying power of the concept is also seen in the way in which
the study of evolution makes a call upon the most diverse fields of
biological study and links them together in solving its problems. Com-
parative anatomy, embryology, natural history and ecology, classifica-
tion, palaeontology, genetics and cytology, the study of behaviouró
all these and many more are now meeting and illuminating each other
in the new evolutionary synthesis.
Evolution, too, was one of the first branches of inquiry to demand
that relativist point of view which is becoming increasingly central
to the modern scientific outlook. The single organism, looked at
through evolutionary spectacles, has no meaning except in relation
to a particular environment, to a particular set of enemies and com-
petitors, to a particular past history, and to a particular set of poten-
tialities for the future. All this was implicit in Darwin's masterly
formulation of the problem.
The implications for man and for his general conception of nature
and of his own place in nature are equally far-reaching. The idea
of a past Golden Age vanished into smoke; so did all static con-
ceptions of human life. In their place we see inevitable change and
possible progress, while at the same time the time-span of the human
drama is enlarged a thousand-fold in the past and still more in the
future.
Newton showed that the same general principles applied to the
motion of heavenly bodies and to that of the humblest terrestrial ob-
jects. Similarly, Darwin, with his few simple principles of the struggle
for existence, natural selection, and consequent adaptation, linked
man with all the rest of life, from monkeys and flowers to bacteria
and amoebae, in a common web of necessity and change. The funda-
mental principles of Newtonian physics have now been superseded
(though it still remains as the most effective first approximation to
physical truth). Though Darwin's principles have been more modi-
fied in detail than Newton's, there seems less likelihood of their being
superseded by a different set of basic principles. There are no signs
that evolutionary biology will not indefinitely remain Darwinian.
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